A man charged with sending letters laden with the poison ricin to President Barack Obama and Sen. Roger Wicker (R-Miss.) was released Tuesday as the investigation apparently zeroed in on one of the former suspect’s rivals.

Federal prosecutors dismissed all charges against Paul Kevin Curtis, a musician and Elvis impersonator from Tupelo, Miss., who was charged last week with two counts of sending threats through the mail.

As Curtis was freed, The Associated Press reported James Dutschke said the FBI was searching his home in connection with the ricin letter case. There was no announcement of any charges filed against Dutschke as of Tuesday evening.

Dutschke, who ran unsuccessfully as a Republican for the Mississippi House of Representatives in 2007, has denied to multiple news organizations that he had anything to do with the ricin letters.

Federal authorities were tight-lipped about the abrupt change in direction of the high-profile case.

“The ongoing investigation has revealed new information,” Felicia Adams, the U.S. attorney for the Northern District of Mississippi, said in a legal motion asking to dismiss the criminal complaint against Curtis.

During a hearing held Friday and Monday in federal court in Oxford, Miss., an FBI agent acknowledged that lab tests detected no ricin in Curtis’s home or car.

At a news conference after his release, Curtis and his lawyers said they did not blame federal agents for investigating him and said the episode seemed to be the result of a long-standing obsession that Dutschke has had with him.

“I understand why anybody out there looking at this would say, ‘We got to look at this guy. We got to investigate this,’” said Curtis.

In rambling answers to questions from journalists, Curtis said he had sent letters to a variety of public officials describing a wide variety of grievances and always signed them: “This is KC and I approved this message.”

He’s also posted similar messages on public websites. However, Curtis’s lawyer said he never sent any threats or prepared any poison, such as ricin, which can be extracted from castor beans.

“That is so not Kevin, to spend hours focused on trying to make ricin [when] he could be off singing,” attorney Christi McCoy said.

McCoy credited prosecutors and investigators for being open to the possibility they had arrested an innocent man.

“Just as quickly as they targeted and zeroed in on Kevin, they were also quick when they realized it just wasn’t him. They were quick and faithful in discharging him,” the defense lawyer said. “I believe they have found a link that will exonerate Kevin and at the same time, show who the true perpetrator is.”

However, McCoy also said she had spoken with some law enforcement officials who thought it had simply been too easy to solve the case and wondered why a person would sign potentially deadly letters with his own initials and favored catchphrase.

Curtis signaled no bitterness at authorities over the episode.

“I hope my incarceration days are over. I want to move forward. I’d like to see my music career take off,” he added. “The only people who would have me the last 10 years are nursing homes and assisted living.”

During the press conference, Curtis said he was a strong supporter of an anti-abortion group. He also described a series of problems he encountered after asking questions about what he said were body parts he found in a cooler at a hospital where he was working.

The entertainer said that as he was seeking a publisher for a book he had written, the problems intensified.

“Someone would crash into my car, total my car out, burn down my home, car explodes, death threats— it was always a distraction, always. Every single time a publisher called me, I was distracted somehow,” Curtis said. “No matter what obstacles are thrown in my pathway. … I will no longer be distracted. I feel like my book will be published very soon.”